Technique for AT command Handling in relation to an EPS Packet Domain

1. A user terminal, capable of accessing both a General Packet Radio Service (GPRS) packet domain and an Evolved Packet System (EPS) packet domain, and further capable of executing applications that use Internet Protocol (IP) bearers, the applications using AT commands for controlling the IP bearers, the user terminal further comprising: at least one microprocessor; a non-transitory computer readable storage medium, coupled to the at least one microprocessor, further including computer-readable instructions, when executed by the at least one microprocessor, are configured to define, in response to an AT command directed to a definition of a secondary Packet Data Protocol (PDP) context type of IP bearer in the GPRS domain, an EPS Service Data Flow (SDF) type of IP bearer in the EPS domain on the basis of the secondary PDP context.

2. The user terminal of claim 1 , wherein the EPS SDF is defined within an existing Packet Data Network (PDN) connection.

3. The user terminal of claim 1 , wherein each AT command includes a Context Identification (CID) parameter as reference to the PDP context.

4. The user terminal of claim 3 , wherein the computer-readable instructions are further configured to: use the CID parameter included in the AT command as reference to the EPS SDF.

5. The user terminal of claim 3 , wherein the computer-readable instructions are further configured to: use the CID parameter of an EPS default bearer associated with the EPS SDF to link the EPS SDF to a Packet Data Network (PDN) connection associated with the EPS default bearer.

6. The user terminal of claim 1 , wherein the computer-readable instructions are further configured to: define, in response to an AT command directed to the definition of a non-secondary PDP context, an EPS default bearer on the basis of the non-secondary PDP context.

7. The user terminal of claim 3 , wherein the computer-readable instructions are further configured to: use the CID parameter included in the AT command as reference to an EPS default bearer.

8. The user terminal of claim 1 , wherein the computer-readable instructions are further configured to: define an EPS dedicated bearer.

9. The user terminal of claim 8 , wherein the computer-readable instructions are further configured to: define the EPS dedicated bearer in response to an AT command including a Context Identification (CID) parameter; and use the CID parameter included in the AT command as a reference to the EPS dedicated bearer.

10. The user terminal of claim 3 , wherein an EPS bearer and one or more SDFs on the EPS bearer have been established, and wherein the EPS bearer and the one or more SDFs on the EPS bearer are referenced by dedicated CIDs.

11. The user terminal of claim 1 , wherein user terminal operates in a Long Term Evolution (LTE) mode and the user terminal additionally supports a legacy Universal Mobile Telecommunications System (UMTS) mode.

12. The user terminal of claim 11 , when the user terminal is operating in the legacy UMTS mode, the computer-readable instructions are further configured to: interpret each AT command in a manner specified for the GPRS packet domain.

13. The user terminal of claim 11 , wherein the user terminal is capable of performing at least one of a handover and Radio Access Technology (RAT) change between LTE network access and legacy UMTS network access, and the computer-readable instructions are further configured to: map, in a handover scenario in which n PDP contexts have been defined and n EPS SDFs are associated with one EPS bearer in the EPS packet domain before the handover, the n PDP contexts on one PDP context towards the GPRS packet domain.

14. The user terminal of claim 1 , wherein the computer-readable instructions are further configured to: provide a conversion between GPRS Quality of Service (QoS) profiles and EPS QoS profiles.

15. The user terminal of claim 14 , wherein the GPRS QoS profiles are compliant with a 3GPP Release 7 or earlier QoS profile and the EPS QoS profiles are compliant with a 3GPP Release 8 or later QoS profile.

16. The user terminal of claim 14 , wherein the conversion is provided in response to an AT command specifying a QoS profile.

17. The user terminal of claim 16 , wherein the AT command is any of +CGEQREQ, +CGEQMIN, +CGEQOS and +CGEQOSRDP AT commands.

18. The user terminal of claim 1 , wherein the computer-readable instructions are further configured to: provide support for at least one of +CGCMOD AT command and +CGTFT AT command.

19. The user terminal of claim 1 , wherein the computer-readable instructions are further configured to: provide support for +CGACT AT command.

20. The user terminal of claim 19 , wherein the computer-readable instructions are further configured to: send a message relating to an activation of a bearer resource upon activation of the EPS SDF; or send a message relating to a release of a bearer resource upon deactivation of the EPS SDF.

21. The user terminal of claim 5 , wherein the computer-readable instructions are further configured to: send a PDN connectivity request message upon activation of the EPS default bearer; or send a PDN disconnect request message upon deactivation of the EPS default bearer.

22. The user terminal of claim 1 , wherein the AT command is received from, requested by, or triggered by an application.

23. The user terminal of claim 22 , wherein the application is agnostic of whether a to connection to the GPRS packet domain or the EPS packet domain exists.

24. The user terminal of claim 22 , wherein the application is configured to dedicatedly handle EPS dedicated bearers.